Trastuzumab (herceptin) for early-stage breast cancer.

Breast cancer patients who have HER2 gene amplification and, consequently, protein overexpression, generally show an aggressive course with short disease-free and overall survivals. Trastuzumab, a humanized monoclonal antibody against the extracellular domain of HER2 protein, has been shown to benefit patients who have HER2-positive metastatic breast cancer, and recently, the results of five adjuvant trials involving more than 13,000 women have been released. Here, the authors summarize the main results and outline the differences among these trials, which have demonstrated an important role of trastuzumab in the treatment of women who have HER2-overexpressing/amplified early breast cancer.